systemctl: introduce --now for enable, disable and mask

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index 275fdece1e70de1d9534179a925d191f8fa1ae5c..d7a5b20946d886588e9a8541688f6bfd8cde1d6f 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -2766,6 +2766,28 @@ int symlink_atomic(const char *from, const char *to) {
         return 0;
 }
 
+int symlink_idempotent(const char *from, const char *to) {
+        _cleanup_free_ char *p = NULL;
+        int r;
+
+        assert(from);
+        assert(to);
+
+        if (symlink(from, to) < 0) {
+                if (errno != EEXIST)
+                        return -errno;
+
+                r = readlink_malloc(to, &p);
+                if (r < 0)
+                        return r;
+
+                if (!streq(p, from))
+                        return -EINVAL;
+        }
+
+        return 0;
+}
+
 int mknod_atomic(const char *path, mode_t mode, dev_t dev) {
         _cleanup_free_ char *t = NULL;
         int r;
@@ -5414,6 +5436,15 @@ int is_dir(const char* path, bool follow) {
         return !!S_ISDIR(st.st_mode);
 }
 
+int is_device_node(const char *path) {
+        struct stat info;
+
+        if (lstat(path, &info) < 0)
+                return -errno;
+
+        return !!(S_ISBLK(info.st_mode) || S_ISCHR(info.st_mode));
+}
+
 int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) {
         _cleanup_free_ char *s = NULL;
         size_t allocated = 0, sz = 0;
@@ -5683,6 +5714,9 @@ int free_and_strdup(char **p, const char *s) {
         /* Replaces a string pointer with an strdup()ed new string,
          * possibly freeing the old one. */
 
+        if (streq_ptr(*p, s))
+                return 0;
+
         if (s) {
                 t = strdup(s);
                 if (!t)
@@ -5693,7 +5727,7 @@ int free_and_strdup(char **p, const char *s) {
         free(*p);
         *p = t;
 
-        return 0;
+        return 1;
 }
 
 int sethostname_idempotent(const char *s) {